library(leaflet)
library(leafpop)
library(leaflet.mapboxgl) # remotes::install_github("rstudio/leaflet.mapboxgl")

\(\color{darkblue}{\textbf{Zoom}}\)

Default

leaflet() %>% addTiles() %>%
  addMarkers(lng = -74.000060, lat = 40.730910)

Far (zoom = 10)

leaflet() %>% addTiles() %>%
  setView(lng = -74.000060, lat = 40.730910, zoom = 10) %>% 
  addMarkers(lng = -74.000060, lat = 40.730910)

Close (zoom = 100)

leaflet() %>% addTiles() %>%
  setView(lng = -74.000060, lat = 40.730910, zoom = 100) %>% 
  addMarkers(lng = -74.000060, lat = 40.730910)

\(\color{darkblue}{\textbf{Markers}}\)

---

\(\color{dodgerblue}{\textbf{Pinpoints}}\)

quakes %>% 
  leaflet() %>% addTiles() %>%
  addMarkers(lng = ~long, lat = ~lat)

---

\(\color{dodgerblue}{\textbf{Colored Circles}}\)

pal <- colorBin("viridis", domain = quakes$mag , bins = c(4,5,6,10))

quakes %>% 
  leaflet() %>% addTiles() %>%
  addCircleMarkers(radius = 6,
                   color = ~pal(mag),
                   fillOpacity = 0.5,
                   stroke = FALSE) %>% 
  addLegend(pal = pal, 
            values = ~mag, 
            opacity = 0.7, 
            title = "Magnitude",
            position = "bottomright")

\(\color{darkblue}{\textbf{Labels}}\)

---

\(\color{dodgerblue}{\textbf{Popups}}\)

content <- paste(sep = "<br/>",
                 "<b><a href='https://furmancenter.org/'>NYU Furman Center</a></b>",
                 "139 MacDougal Street, 2nd floor",
                 "New York, NY 10012")

leaflet() %>% addTiles() %>%
  addMarkers(lng = -74.000060, lat = 40.730910, 
             popup = content)

\(\color{dodgerblue}{\textbf{Hover Labels}}\)

labels <- sprintf("Magnitude: %g",
                  quakes$mag) %>% 
  lapply(htmltools::HTML)

quakes %>% 
  leaflet() %>% 
  addTiles() %>%
  addCircleMarkers(radius = 6,
                   color = ~pal(mag),
                   fillOpacity = 0.5,
                   stroke = FALSE,
                   label = labels) %>% 
  addLegend(pal = pal, 
            values = ~mag, 
            opacity = 0.7, 
            title = "Magnitude",
            position = "bottomright")

---

\(\color{dodgerblue}{\textbf{Formatting}}\)

leaflet() %>% addTiles() %>% setView(-118.456554, 34.09, 13) %>%
  addMarkers(lng = -118.456554, lat = 34.105,
             label = "Default Label",
             labelOptions = labelOptions(noHide = T)) %>%
  addMarkers(lng = -118.456554, lat = 34.095,
             label = "Label w/o surrounding box",
             labelOptions = labelOptions(noHide = T, 
                                         textOnly = TRUE)) %>%
  addMarkers(lng = -118.456554, lat = 34.085,
             label = "label w/ textsize 15px",
             labelOptions = labelOptions(noHide = T, 
                                         textsize = "15px")) %>%
  addMarkers(lng = -118.456554, lat = 34.075,
             label = "Label w/ custom CSS style",
             labelOptions = labelOptions(noHide = T, 
                                         direction = "bottom",
                                         style = list("color" = "red",
                                                      "font-family" = "serif",
                                                      "font-style" = "italic",
                                                      "box-shadow" = "3px 3px rgba(0,0,0,0.25)",
                                                      "font-size" = "12px",
                                                      "border-color" = "rgba(0,0,0,0.5)")))

\(\color{darkblue}{\textbf{Polygons}}\)

---

pal <- colorBin("viridis", domain = population$legend_value)

labels <- sprintf("<strong>%s</strong><br/>Population: %s",
                  population$NAME, population$pretty_estimate) %>% lapply(htmltools::HTML)

population %>% 
  leaflet() %>% addTiles() %>% setView(-96, 37.8, 4) %>% 
  addPolygons(fillColor = ~pal(legend_value),
              fillOpacity = 0.7,
              color = "white",
              weight = 1,
              opacity = 1,
              smoothFactor = 0.5,
              highlight = highlightOptions(weight = 5,
                                           color = "white",
                                           fillOpacity = 0.7,
                                           bringToFront = TRUE),
              label = labels,
              labelOptions = labelOptions(style = list("font-weight" = "normal", 
                                                       padding = "3px 8px"),
                                          textsize = "15px",
                                          direction = "auto")) %>% 
  addLegend(pal = pal, 
            values = ~legend_value, 
            opacity = 0.7, 
            title = "Population (Millions)",
            position = "bottomright")